I recently completed the PADI Tec40 course, the first level of their technical diving training. For those of you who don’t know, technical diving is any diving which goes beyond recreational limits, generally either because it exceeds no-stop times and therefore requires decompression stops, or because it requires deep penetrations into overhead environments (wrecks and caves). The defining feature really is the lack of direct access to the surface in an emergency, either due to a physical barrier like being in a cave, or a theoretical barrier like the requirement to do a decompression stop. Being unable to simply abort a dive and swim to the surface drastically changes the way divers have to prepare and train, since what would be a minor problem on a normal dive such as a regulator free-flow or a lost mask could be disastrous if you still have a long decompression obligation ahead of you.
This is why technical divers use slightly different equipment and procedures to recreational divers, and the training is about as extensive as learning to dive again from scratch (just the Tec40 course is about the same length as re-doing Open Water).
So why did I do the course? As the manual makes clear, technical diving is inherently more risky, considerably more mentally and physically demanding, and is absolutely not required to enjoy a long and diverse career as a recreational diver. However, from the first time I looked at the course details it immediately appealed to me for several reasons.
Developing fundamental skills
Many of the skills emphasised by the Tec40 course are those that all divers should have but sadly many never develop fully and aren’t always emphasised enough in the initial training. Buoyancy control, for example, is often skated over in Open Water and Advanced Open Water and left to divers to develop, or not, in their own time. Little wonder that so many never really do perfect it, and simply maintain depth through constant finning. This isn’t an option for technical divers. For one thing they move with gentle and infrequent frog kicks to avoid kicking up silt in a cave or wreck. More to the point, you cannot possibly do a safe air switch or long decompression stop if you cannot maintain a steady depth with little or no effort.
Other skills the course develops are things like deploying an SMB, more self-rescue, swimming without a mask, having a full understanding of the effects of different gas mixes at different depths and how to do the relevant calculations, and extensive multi-level repetitive dive planning. All of this is relevant and important for recreational divers. Of course, that’s not to say that a Tec course is the only or even the best way to learn these skills. It’s certainly not designed as an advanced recreational qualification. However knowing that I could pursue my interest in doing occasional advanced dives but also improve valuable skills for my more frequent recreational-limit diving made the course particularly appealing.
The Tec 40 course doesn’t in fact allow greater depth than the deep diver speciality, which is a prerequisite anyway, but it does allow you to spend considerably longer at that depth by teaching you to plan for up to ten minutes of decompression. The extra flexibility to spend more time at depth is a game-changer as, on my final check dive we floated peacefully around at 40 metres for what seemed like ages, hunting for dropped GoPros (sadly didn’t find any), largely undisturbed by the recreational divers with their small tanks and tight no-stop limits who either never came down that deep or else came and quickly left.
Technical diving opens so many more options, whether it is penetrating further into wrecks or caves, going deeper, or just being able to stay long enough to hunt down that perfect photo. Diving already lets you go places where few other people can, but technical diving puts you into an even smaller group going places even less-frequented. That’s a hugely appealing feeling, although I admit that some of my enjoyment of being at 40 metres for so long may have been down to a touch of narcosis…
Learning new skills and mastering new equipment
I enjoy challenging myself and learning to do things that are initially tricky. Mastering the maths involved in technical dive planning, and the physical skills involved in gas shutdowns and NO TOX switches is hugely satisfying. Tec diving also teaches new ways of thinking about dive planning, safety and equipment which I hope will make me a better diver even when applied to recreational diving. And of course it involves new equipment; double-bladder wing BCDs, twin cylinders with an isolated manifold, decompression and stage cylinders, and differently rigged second-stage regulators. The new equipment is all there for a reason and that reason is to add an extra layer of safety and put you as a diver more in charge of your own safety, rather than relying on your buddy as your first port of call in an emergency. It all takes time to master, of course, but I like that feeling of constantly pushing to improve, rather than letting my skills stagnate as I do the same kind of dives year after year.
As I say (and as the training manual says) Tec diving absolutely isn’t for everyone. This blog post isn’t intended to in any way imply that all divers should do it, I’m simply explaining my own motivation for it. However, if you are finding that your standard recreational limit dives are becoming a little stale, and you like the idea of pushing yourself, learning new skills and polishing old ones, it’s well worth looking at a technical diving course.